Tuesday, March 25, 2008

Tarvaris Jackson: 8-4get about the record

I could have titled this entry "Myths in Sports: Quarterback win-loss record," but I didn't want aajoe7 suing me for copyright infringement. Still, that's essentially the thrust of the next few paragraphs: to prove that the oft-quoted line about Tarvaris Jackson having an 8-4 record as the Vikings' starter in 2007 -- about the only positive one can say about his season -- is virtually meaningless, no matter how often coach Brad Childress wants to shove it down our throats as justification for Jackson's remaining the starting quarterback.

A quarterback's win-loss record is about as meaningful as the win-loss record of a starting pitcher, if not less so. The most basic assumption is that offense and defense, in any sport, have equal importance. A quarterback has an effect on his team's offense. He has virtually no effect on his team's defense. (Yes, I know that turnovers deep in one's territory can affect how many points a defense gives up. But then you'd also have to give the defense credit for getting a turnover at the opponent's 10-yard line. Over the course of a season, it's reasonable to assume those opportunities cancel each other out.) Right there, that takes 50% of the outcome of a game from the quarterback.

Then there's the running game. Peyton Manning hands off pretty much the same as Trent Dilfer. Last season, there were 18,147 pass plays (attempts plus sacks) and 13,986 rushing plays called. Some of the runs were by quarterbacks, but that still puts the league at a 56% passing rate. 56% of 50% is 28%.

You could stop here. Even skeptics would agree that defense is just as important as offense and that the QB has virtually no effect on the running game or defense. But you can still pare it down further.

Then there's the impact of other players on the offense. Even the best quarterback can't put up numbers if his line doesn't block and his receivers can't catch the ball. At best, quarterback and receiver each have to make a play, and you could argue that their effect on a play is equal. That cuts the quarterback's usefulness in half again, from 28% to 14%. Figure in line play and the QB's effect on the game probably drops to about 10% or so.

So, does that mean that a quarterback only has about a 10% chance of affecting the outcome of a game? Maybe. But even if that's the case, it doesn't mean the position is overrated (well, maybe a bit). If you consider a team to have 24 starters -- 11 on each side of the ball, plus kicker and punter -- then, if all were equal, you'd expect each to have a 100%/24 = 4.2% effect on the outcome of the game. A quarterback, then, is two to three times as important as the "average" player. Some of this also depends on the role the QB is expected to play on a team. Peyton Manning, for instance, is certainly worth more to his team when they pass a lot or have a weak defense, as was essentially the case in 2006. On a team that relies on its running game or defense, the quarterback is less important.

All of which brings us back to T-Jack. Let's take a look at "his" eight wins from 2007 to see just how important he was:

Week 1 (Atlanta): 24-3
Defense holds Atlanta to 3 points, returns two interceptions touchdown. Adrian Peterson runs 60 yards on a swing pass for Jackson's lone TD pass. His final numbers are 13-23, 163 yards, 1 TD, and 1 Int.

Week 6 (Chicago): 34-31
Peterson rushes for 224 yards, has 363 all-purpose yards (only 11 on receptions). Jackson is 9-23 for 136 yards and 1 TD, including a 60-yard bomb to Troy Williamson.

Week 9 (San Diego): 35-17
Peterson rushes for 296 yards. Jackson is hurt in the second quarter, goes 6-12 for 63 yards.

Week 11 (Oakland): 29-22
Sidney Rice starts the game with a 79-yard trick pass to Visanthe Shiancoe. Chester Taylor rushes for 164 yards. Jackson is 17-22 for 171 yards and 1 Int.

Week 12 (NY Giants): 41-17
Defense picks off Eli Manning four times, returning three for TDs. Jackson is 10-12 for 129 yards and 1 TD.

Week 13 (Detroit): 42-10
Peterson and Taylor combine for 186 rushing yards. Aundrae Allison returns a kick for a TD. Jackson is 18-24 for 204 yards, 2 TDs, and 1 Int.

Week 14 (San Francisco): 27-7
Trent Dilfer starts for 49ers, guaranteeing Viking victory. Defense forces 5 turnovers, Chester Taylor scores on 84-yard TD run. Jackson is 16-25 for 163 yards and 1 TD.

Week 15 (Chicago): 20-13
Defense holds Bears to 209 yards. Peterson rushes for 78 yards and 2 TDs. Jackson is 18-29 for 249 yards and 3 Ints.

So there you have it. Of Jackson's 8 "wins," only three were close, and most were dominated by strong play from the defense or the running game. Statistically, Jackson's best game was the Detroit contest, but if the best you get from your QB is 18-24, 204 yards, 2 TDs, and 1 Int., then you might have a problem. And in some of those games -- the second Chicago contest, in particular -- he was average to bad but was bailed out by the rest of his team. And all this doesn't take Jackson's 4 "losses" into account, like a 6-19 performance against Dallas in which Bobby Wade was said to remark, "If you start throwing it at us, we'll start catching it." Then there was the four-interception game against Detroit back in week 2.

In Jackson's so-called "good" stretch, the five-game winning streak, he went 79-112 for 916 yards, 4 TDs and 5 Ints. That's a fine 70% completion percentage and 8.2 yards per attempt, but the 88.2 passer rating is only above average. If he could play like that over a whole season, things would be fine, but there's been little to show that would be the case. Plus, only two of those five games were close. In the Chicago and Oakland games -- which a good quarterback would have put away easily -- Jackson had zero TDs and four interceptions, allowing the inferior team to stick around until the final quarter.

All this isn't to say that Jackson shouldn't be the Vikings QB. Again, if he can show the skills and patience he displayed over that winning streak, with the team assembled around him, he can at least be an above-average QB with a great supporting cast. And the addition of Bernard Berrian should be a boon to the weak WR corps. But please, the next time you hear someone say Jackson should be the starter because he was 8-4 in 2007, just remember that Trent Dilfer once "won" a Super Bowl and that Jose Lima once "won" 21 games.

2 comments:

Anonymous said...

You forget in your 4.2% of affecting the game that the quarterback touches the ball on virtually all offensive plays. That is all plays that either the defense or kickers [from either team] are not on the field. I am not a T-Jack apologist, but there are other non statistical elements that also weigh into the equation, like leadership and communication skills.

You can have the greatest field general in the history of the world go to battle, but if he does not have a sizeable army adequately equipped to meet the enemy, he will lose the war. On the other hand if you have the fully sized and well equipped army, even a less experienced field general, especially with good plans from the chief of staff, he can execute a victorious campaign. In the mean time this second general can work through and learn from his mistakes, and get better.

That my friend is where I view Tarvaris. He is somewhat well equipped but is missing the strategic ability to strike deep… Enter Bernard Berrian. He has a higher authority passing out a “Kick Ass” game plan (that tends to not to look be able to adjust in mid-battle). T-Jack should show further signs of improvement, but you are correct, it is not all him, the rest of the team must do their part from the ball boys to Childress and the front office for the team to be successful. 8-4 is not just T-Jack but everyone else too and it is too bad that Childress either doesn’t see that, or isn’t bright enough to articulate it and tries to put it all on #7.

Jason said...

I'm no fan of the "touch the ball on every snap" argument either. You or I could hand off (well, maybe with a little practice) as well as just about any NFL QB, too. The center touches the ball on every snap, too.